EEGs Flashcards
For a sharp wave to be apparent, at least
___ cm2 of cortex needs to be involved
6cm2
The parasomnias associated with slow wave sleep are? (3)
sleep walking, night terrors, bedwetting
Frontal lobe seizures are typically nocturnal and arise from what stage of sleep?
stage II
What is Mu rhythm?
is normal, and found in the central derivations (C3/C4) over the motor strip. Can be bilateral or unilateral. Attenuates with movement or even the thought of movement.
Wicket spikes are found in which electrodes?
Mid-temporal electrodes
Normal response to hyperventilation on EEG?
High voltage theta activity (children are more likely to achieve this than adults)
What is a photomyogenic response? How is this different from photic driving?
EEG artifact in the frontal derivations time locked to the flash frequency.
Photic driving:
Photic stimulation can evoke a rhythmic frequency in the occipital derivations which is at same frequency (the fundamental), a harmonic (twice the flash frequency) and/or a subharmonic (half the flash frequency).
in a normal infact, sleep spindles typically develop at what age?
1.5 - 3months
Why are sleep spindles not synchronous in infants?
due to lack of myelination in the neonatal brain. By 2 years of age, it is considered abnormal if most spindles are still asynchronous.
Majority of children will have a PDR of 8Hz by what age?
36 months
What are BIRDs?
brief potentially ictal rhythmic discharge (BIRD) in the alpha and theta range. BIRDs are very brief (less than 10 seconds, typically 0.5–4 seconds) runs of rhythmic activity greater than 4Hz without evolution. They can be lateralized or generalized and are highly correlated with the seizure focus.
what seizure aura can be mistaken for panic attacks?
Very brief, in the order of seconds, sensations of fear are a common aura of a mesial temporal lobe seizure and can be mistaken for panic attacks.
What is Panayiotopolous syndrome?
children present with rare prolonged nocturnal seizures with autonomic features and eye deviation.
A strong sensation of being pursued by a predator who is behind and on the left is most consistent with a seizure from the
the ipsilateral amygdala
The triad of West syndrome is….
infantile spasms, hypsarrythmia, and developmental delay and/or regression
Treatment of hypsarrhythmia?
ACTH
Leucine-rich, glioma inactivated 1 (LGI1) gene.
Autosomal dominant partial epilepsy with auditory features
Heat sensitive seizures, hemi-convulsions, myoclonic seizure, atypical absence, ataxia, and neurological regression.
Dravet syndrome
Hypsarrhythmia, infantile spasms, developmental regression and delay.
West syndrome
Occipitally predominant generalized rhythmic delta activity (aka OIRDA-occipital intermittent rhythmic delta activity).
childhood absence epilepsy
Myoclonic jerks, absence seizures, generalized tonic clonic convulsion
JME
Language regression, electrical status epilepticus in sleep.
Landau–Kleffner syndrome
Tonic seizures, burst suppression, abnormal CT head.
Ohtahara syndrome
Slow spike and wave, multiple seizure types, cognitive impairment.
Lennox–Gastaut syndrome
he EEG shows continuous 1–2 Hz generalized periodic discharges often with a triphasic morphology and sometimes with an anterior to posterior lag (box shows a wave with an A-P lag). This is most consistent with
toxic metabolic encephalopathy
LPDs are most commonly associated with
cute, structural lesion involving the cortex. Therefore, other findings of focal dysfunction such as focal slowing or attenuation are frequently accompanied in the ipsilateral hemisphere. The most common etiology of LPDs is an ischemic stroke. Other frequent etiologies include viral encephalitis, brain tumors, brain abscesses and intracranial hemorrhages.
MRI shows diffusion restriction in the caudate and in the putamen as well as hyperintense signal in the cortex (cortical ribboning). The EEG shows generalized periodic sharp waves at 1–2 Hz that are either biphasic or triphasic (GPDs) on a suppressed background. What is the diagnosis?
CJD
